THIS PROJECT CONTINUES OUR DEVELOPMENT NEW METHODS FOR THE SYNTHESIS OF LABELED PRECURSOR COMPOUNDS. OVER THE YEARS SIR HAS DEVELOPED EFFICIENT METHODS FOR THE SYNTHESIS OF 13C-LABELED ONE-CARBON PRECURSORS METHANE, METHANOL, METHYL IODIDE, FORMATE, POTASSIUM CYANIDE, AND CARBON DIOXIDE FROM [13C]CARBON MONOXIDE. THESE ONE-CARBON PRECURSORS FORM THE FOUNDATION OF ALL 13C LABELING CHEMISTRY. MISSING FROM THIS GROUP ARE PRECURSORS AT THE OXIDATION STATE OF FORMALDEHYDE. WE ARE DEVELOPING T-BUTYL [13C]METHYL ETHER AS A ONE CARBON PRECURSOR. TREATMENT OF T-BUTYL METHYL ETHER WITH SCHLOSSER'S BASE (SEC-BUTYL LITHIUM/POTASSIUM T-BUTOXIDE) RESULTS IN THE POTASSIUM ANION OF T-BUTYL METHYL ETHER WHICH CAN BE CONSIDERED A FORMALDEHYDE SYNTHON. WE HAVE USED THIS SYNTHON AS A PRECURSOR FOR THE SYNTHESIS OF LABELED GLYCOLIC ACID, DIHYDROXYACETONE, DIHYDROXYACETONE PHOSPHATE, AND GLYCEROL. WE WILL CONTINUE TO EXPLORE THE UTILITY OF THIS PRECURSOR IN LABELING CHEMISTRY.